Series and Parallel Demand Sharing in Multi-Boiler System

Abstract

A boiler is an enclosed vessel that provides a means for heat of combustion to be transferred into water until it becomes heated water or steam. The hot water or steam under pressure is then usable for transferring the heat to a process. The requirement of steam or hot water i.e. process requirements keep on varying throughout the day. This also implied that load on the boiler may not be same at all the time. Therefore, more than two boilers of different capacities can be operated. A suitable combination of boilers can be chosen to get the desired load. Such a system, generally called as multi- boiler system can be used to improve the efficiency of the plant as a whole. Boiler can be connected in series or parallel. This reduces the overall running cost of the plant. When boiler are connected in series its fuel consumption decreases by 5.5% under increasing load demand and by 6.5% under decreasing load demand as compare to parallel system. The variation in efficiency of multiple boiler system, when operated in series and parallel. When operating at part load conditions, the parallel strategy for multiple boiler system gives better efficiency than the series strategy. Hence the optimum solution for operation of multiple boiler system in steam plant is to operate with series load management strategy.